/Engine/Plugins/Developer/Concert/ConcertApp/MultiUserClient/Source/MultiUserClientLibrary/Public/MultiUserClientStatics.h
Enum of the known Multi-User connection error, their value needs to match the internally returned error code.
enum EMultiUserConnectionError { None = 0, Canceled = 1, ConnectionAttemptAborted = 2, ServerNotResponding = 3, ServerError = 4, WorkspaceValidationUnknown = 100, SourceControlValidationUnknown = 110, SourceControlValidationCanceled = 111, SourceControlValidationError = 112, DirtyPackageValidationError = 113, }